This invention relates to chewing gum. More particularly, it relates to chewing gum (especially sugarless gum) with improved sweetness, employing xylitol as a rolling or dusting compound.
For many years it has been known to dust products such as chewing gum with materials such as powdered sugar to improve appearance and initial taste. The dusting also is intended to prevent the chewing gum from sticking to the fingers when handled, or to the wrapper when the product is unwrapped. The material used to dust chewing gum is known as a dusting compound; or, because its primary function in gum is to make the gum more manageable during processing, including rolling, as a rolling compound.
Frorer, in U.S. Pat. No. 2,305,96O, issued Dec. 22, 1942, discloses the use of mannitol crystals as a dusting compound for chewing gum and other products, to retain its appearance, palatableness and resistance to stickiness in humid weather. The chewing gum is dusted over its entire exterior surface with mannitol crystals, and the dusted sheets are cut and wrapped. Application can also be made by dipping the gum in the mannitol crystals, or by sprinkling the mannitol crystals on the gum.
Other conventional known rolling compounds include sucrose, sorbitol, starch calcium carbonate and talc. Sucrose is a sugar, and by definition, cannot be used in a sugarless gum. Mannitol is today the most common sugarless rolling compound but it does not enhance initial sweetness of the chewing gum. Sorbitol can cause a burning sensation in the throat. Starch can give a dry mouth feel and can cause embrittlement of the gum by drawing water out of the gum stick. Calcium carbonate and talc likewise do not enhance taste.
Arnold et al., in U.S. Pat. No. 4,562,076, issued Dec. 31, 1985, disclose the application of thaumatin or monellin, alone or in combination with other known rolling compounds, to the surface of chewing gum, as high-potency flavor and sweetness enhancers.
Fronczkowski et al., in U.S. Pat. No. 4,127,677, issued Nov. 28, 1978, disclose a xylitol-coated chewing gum, made by applying a coating syrup of 55-70 percent solids, of which solids 95-99.5 percent is xylitol. No dusting or rolling compounds are mentioned, and in fact, the gum centers are dedusted before applying the coating syrup. The amount of coating is not explicitly stated, but the coating solution is said to be sprayed onto gum centers "until the desired weight or gauge is reached". Sufficient coating is applied to allow polishing, and a smooth, bright white coating, substantially free of imperfections, is obtained (col. 4, lines 26-31 and 56-58). In distinction to the present invention, moreover, the xylitol of the Fronczkowski et al, gum product is not present in particulate form, but rather as a coherent coating which has been dried from a syrup.
Hammond et al., in U.S. Pat. No. 3,899,593, issued Aug. 12, 1975, disclose a chewing gum composition containing a major amount of xylitol. The composition of U.S. Pat. No. 3,899,593 requires from about 2 to about 6% by weight of glycerol, "in order to soften the gum base to the extent that the base will be capable of binding the crystalline material," (col. 1, lines 64-65 and col. 2, lines 19-21).
Reggio et al., in U.S. Pat. No. 4,065,578, issued Dec. 27, 1977, disclose a chewing gum composition wherein xylitol is used as a major bulking sweetening agent, and a hydrocolloid is used as a binder between the gum base and xylitol. The hydrocolloid also serves as a humectant to hold moisture in the gum (col. 1, lines 27-32). Both U.S. Pat. Nos. 3,899,593 and 4,065,578 teach that a binder is necessary to produce a gum product with xylitol as the major bulking agent.
Klose et al., in U.S. Pat. No. 4,000,320, issued Dec. 28, 1976, and reissued Jan. 22, 1980 as U.S. Reissue Pat. No. Re. No. 30,197, disclose a chewing gum composition containing less than 50% xylitol; and as stated in the Examples and in the Reissue Patent at col. 1, line 68--col. 2, line 2, preferably less than 10% by weight, especially from 1 to 3.2% by weight. Klose et al. use xylitol to extend the storage stability of the gum, by enabling the gum to retain more moisture when the gum is stored at low relative humidities (col. 2, lines 51-57; reissue at col. 2, lines 64-67).
Bohni, in U.S. Pat. No. 3,914,434, issued Oct. 1, 1975, discloses the use of xylitol as a non-cariogenic sugar substitute.
Glass et al., in U.S. Pat. No. 4,374,858, issued Feb. 22, 1983, disclose a rolling compound comprising aspartame for stabilizing aspartame in gum.